Healing: How long will it be before I can play contact sport again?

The answer to this question in general is that return to sports is permissable when the fracture is healed and consolidated. Since this is different for every fracture and every individual you should discuss the issue personally with your OS.
Healing means that bone has developed in the scar tissue that bridges the fracture. This binds the bone fragments together with a rigid bridge of callus or woven bone. There may be evidence of bridging callus as early as 6 weeks post fracture in an adult (an earlier in children).
Consolidation of the fracture means transformation of the woven bone into consolidated dense bone which approximates the normal bone present before the injury. This takes much longer (months) and is much more related to the anatomy of the fracture.
Generally speaking a fracture that still hurts with activity is still healing, perhaps in the stage of consolidation. However, hardware can hurt even after healing is completed; so there is some doubt which needs expert assessement and advice from your OS. The question of whether to have hardware removed is discussed elsewhere in this section.
Myles Clough MD 20 Jan 2002From: Paul Clegg

I broke my tib. and fib. in mid-September last year (2001)playing 5-a-side football (shin to shin collision). I had an IM rod and screws put in and am now walking quite well, though still not at my normal speed. I am due to start back at the gym where I will do some light walking, etc. Firstly, I wish to play football again and want to know when, in your view, this would be possible. Secondly, does the metalwork need to come out prior to the above?